Process for preparing water-softening material



Patented Aug. 13, 1929.

UNITED STATES GEORGE W. PRATHER, OF DENVER. COLORADO.

PROCESS FOR PREPARING WATER-SOFTENING MATERIAL.

No Drawing. Original application filed August 10,

1916, Serial No. 114,271, now ratent No. 1,636,942.

Divided and this application filed July 15, 1927. Serial No. 208,140.

My invention relates to a process for preparing a water softeningmaterial.

My present application is a division of my application filed August 10,1916, Serial No. 114,271, for a process for treating a naturalzeolite-like substance to render it capable of softening water.

In carrying out my invention a' mineral, which has for its base ahydrated silicate of aluminum, containing a small amount of impuritiesand some moisture, is reduced to about the size of an English walnut,placed in a 10% salt solution at .a temperature of about 200 degreesFahrenheit; kept there 5 for about two hours, and is then placed ondriers and allowed to dry in the open air for about 30 days, or untilpractically all the uncombined moisture is driven ofl. The material isthen dried by artificial heat until the remainder of the moisture isdriven ofit'y The material issubsequently reduced to particles ofsuitable size by mechanical means, and an alkali metal compound is addedand mixed therewith. The mixture is then baked in an oven or furnace ata high temperature until the mineral is hard enough to resist thewdering action of water. During the ba 'ng, the alkali metal compoundmelts and thoroughly permeates th particles of mineral. Finally themineral is washed free of excess alkali compound and is then dumped intoa vat of salt water and stored there. Suitable alkali metal compoundsfor incor orating in the mineral are the hydroxides ofpotassium andsodium and the carbonates of potassium and sodium, or

a mixture of two or more of such compounds.

I find that the-desired results may likewise be secured by taking thenatural zeolite-like substance, having for its base a hydrated silicateof aluminum containing a small amount of impurities and some moisture,and drying thesame at a low temperature either in the air by the heat ofthe sun or by artificial heat until all of theunoombined water isremoved, after which the material is baked at a high temperature in anoven or furnace until the mineral is hard enough to resist the powderingaction of water. The mineral is then dumped into a vat of salt water andstored there.

Either of the above described treatments of the material renders itgranular and rous and of such a nature that it is'hig l efiicient as awater softener. The materia,

. drated silicate of aluminum until practically while stored in the saltwater, gives off such calcium and magnesia as is contained there- 1n. Itis then capable of absorbing from any water passed through it allcalcium and magnesia contained in the water, and leaving a pure,softened water. a

After the mineral has absorbed all the calclum and magnesia salts thatit is capable of absorbing, said salts may be removed from the mineralby treating the same with a solution of salt water, thereby restoringthe mineral to its full capacity for softening water. Since the calciumand magnesia taken up by the mineral may be thus removed, and since thetreatment given the mineral renders it nonreducible under the action ofwater, it follows that the life of the mineral is very great.

My invention. further contemplates the boiling of the mineral in theinitial salt solution, and then contemplates the storing of the mineralin a dry condition instead of in salt Water, where desired.

Having described my invention what I claim is new and desire to protectby Letters Patent is:

1. The process for forming a filtering and water softening materialwhich consists in drying a mineral having for its base a byall theuncombined moisture is driven o reducing such mineral to particles ofsuitable size for use in granular bed filters by mechanical means, thenbaking such mineral at a high temperature in the presence of an alkalimetal carbonate until the carbonate melts and thoroughly permeates themineral and the particles are rendered hard, and

' finally washing the mineral free ofexcess of the carbonate employed.

2. The process for forming a filtering and water softening mineral whichconsists in drying a mineral having for its base a hydrated silicate ofaluminum until racticalliy all the uncombined moisture is riven o 10oreducing such mineral to particles of suitj able size for use ingranular bed filters, by mechanical means, then baking such mineral at ahigh temperature in the presence of sodium carbonate until saidcarbonate melts and thoroughly permeates the mineral, and finallywashing-the mineral free ofexcess of sodium carbonate.

3. The rocessfor formin a filtering and water softening material 111 asuitable mineral which consists in reducin said mineral to particles ofsuitable size or use in a granular bed filter by mechanical means, thenadding an alkali metal carbonate to the mineral particles, and bakingthe mixture at a temperature sufiiciently high to render 'the particleshard enough to resist the wdering action of water, and finally was ingthe particles .free of excess carbonate ofthe alkali metal.

4. The process for forming a filtering and water softening material froma natural silicate mineral which consists in reducing said mineral toparticles of suitable size for use in granular bed filters by mechanicalmeans, then adding sodium carbonate to the mineral particles, and bakingthe mixture at a temperature sufiiciently high to liquify the carbonateand render the particles hard enough to resist the powdering action ofwater, and finally washing the particles free from excess sodiumcarbonate.

5. The process for forming a filtering and water softening material fromnatural silicates of aluminum which consists in mixing with saidsilicates an alkali metal compound other than sodium hydroxide, andbaking the mixture at a; temperature sufliciently mineral a non-acid,soluble alkali metal com-' pound and baking the mixture at a temperaturesufficiently high to liquify the alkali ,metal compound and cause it topermeate the material, and sufliciently high to render the material hardenough to resist the powdering action of water, and finally washing thematerial free from excess alkali metal. In testimony whereof, I havehereunto signed my name to this specification.

GEURGE W. FEATHER.

